This research, using a prospective longitudinal design, examines the effects of early work experiences on adolescent mental health. A panel study is currently in its fourth year, with annual surveys obtained from 1001 adolescents during each year of high school. The central hypothesis is that the mental health consequences of work are dependent on the nature of work experiences, especially the opportunities, stressors, autonomy, and social support encountered in the workplace. Work experiences are expected to influence the adolescent largely indirectly, through their effects on attitudes and behaviors with respect to the family, school and peer group. Mental health indicators under investigation are depressive affect and well- being, self-derogation and self-esteem, and personal efficacy (mastery orientation). Outcomes relevant to present and future adjustment are also assessed: e.g., educational aspirations, academic achievement, school problem behavior and substance use. Finally, the research examines factors which influence selection into work and changes in work experiences over time. Particular features of work experience that influence boys' and girls' mental health and behavioral adjustment through the tenth grade of high school have been identified and some intervening mechanisms assessed. Continuing support is requested: (1) to analyze four waves of data, to more fully understand the impacts of adolescent work, including critical intervening variables and potential interactions (e.g., differences in its effects, depending on timing; subgroup variation; and support in the domains of family and school); (2) to conduct a fifth wave of data collection, four years most respondents' graduation from high school, to assess longer-term consequences. This survey will enable assessment of whether early work constitutes a source of stress resistance, "steeling," or protection in the face of subsequent life stressors, especially those encountered in work situations. Alternatively, it could be a stress-sensitizing factor, if it has occurred at a time when the adolescent is not "developmentally ready." A component of this research examines processes of adaptation, acculturation, and mental health through adolescence and the transition to adulthood in a recent immigrant group of Hmong refugee adolescents.